Adjustable drill and counterboring tool



Sept. 7 1926.. 3,598,726

H. E. JAYNES ADJUSTABLE DRILL AND COUNTE'RBORING TOOL Filed Feb, 12, 1926 2 Sheets-Sheet 1 LYIVIYTOR 4-1 TTORNEY.

Sept. 7 1926.

H. E. JAYNES ADJUSTABLE DRILL AND COUNTERBORING TOOL Filed Fb 12, 1926 2 Sheets-Sheet 2 11W EN TOR A-I 'IYURNI'IS Patented Sept. 7, 1926.

UNITED STATES PATENTQFFICE.

HOWARD EL JAYNES, OF DETROIT, MICHIGAN.

ADJUSTABLE DRILL AND COUNTERBOKING TOOL.

Application filed February 12, 1926. Serial 1T0. 87,758.

This invention is especially designed for woodworkers use,-it may however be employed as a metal working t'ool.

One of the objects of this invention is to provide an adjustable drill and counter-boring tool which may be readily adjusted to receive and grip drills of varying dlameter to bore either a plain hole to receive roundhead screws or a hole and counter-bore to receive a flat screw flush with the surface of the wood, or a hole and counter-bore of sufficient depth to receive the head of a flat screw to be covered by a wood veneer or other means for concealing the screw ;-the hole and counter-bore bei'n'g'completed in a single operation.

A further object of the invention is to provide means whereby the depth of the hole bored and also the depth of the counter-bore may be controlled.

\Vhile this device is shown in connection with a hand-drill, it may also be used with a breast, post drill, or other suitable actuating means.

\Vith the foregoing and other'objects in View which will appear as the description proceeds the invention further resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed it being understood that changes may be made in the precise embodiment of the invention herein disclosed without departing from the spirit of the same.

In the drawings accompanying this speclfication:

Figure 1 is a side elevation of the device as it would appear when drilling a hole and counter-bore for a flat headed screw.

Figure 2 is a vertical sectional view through the device shown in Figure 1 with the cutters of the counter-bore adjusted so as to cut a deep seated counter-bore for a fiat headed screw to be afterwards covered by a veneer or other means for concealing same.

Figure 3 is a cross sectional view through a wooden member bored to receive a screw and counter-bored for the head of the screw and covering veneer,provided for by the adjustment of the device as shown in Fig ure 2 .manually turning the latter.

Figure 4 is a side elevation of the device partly in section showing the adjustment of the drill and counter-bore cutter with reference to the end of the slotted spindle, to limit the depth of the bore.

Figure 5) is a similar sectional view showing the device ad'usted to receive a drill of relatively larger iameter.

Figure 6 is a cross sectional view taken on or about line 66of Figure 4.

Figure 7. is" a detail cross sectional view through the rotatable sleeve with parts in elevation showing thegrooves in the sleeve to receive the-drill gr1ppi-n'g jaws and integral counter-bore cutters.

Figure 8 is ,a "perspective view showing one of the? combined drill gripping jaws and counten borecutters Figure 91 is a sectional elevation of the tubular slotted spindle, with parts broken away.

Referring nowto the letters of reference placed upon the drawings:

A denotes the grip .or handle of a handdrill. Bis its driving gear in mesh with a pinion C mounted'on the shank of a screw threaded spindle D-journaled in the sleeve E of the supporting frame. B is a crank for manually actuating the gear. F indicates a chuckincluding a milled head G tapped to receive the spindle D on which the head ,is longitudinally adjusted by H denotes a rotatable sleeve with a tapering bore and inclined grooves to receive a plural number of jaws I adapted when adjusted to grip the shank ofa drill J. The outer end of the jawsare provided with a shoulder I and an extension I. terminated in an inclined cutting edge I for cutting counterbores. The spindle D has a plurality of slots at at its. lower end to receive the jaws I which project through the slots into the inclined grooves h of the sleeve H as previously explained. The spindle D has also a central bored? to receive the shank of the drill J when adjusted longitudinally with reference, to the counter-borin end of the jaws I. K denotes a plurahty of balls lodged in opposing annular ooves respectively formed in the milled ead G and the upper end of the rotatable sleeve. The sleeve H-has aprojecting flange with an inclined under-face H, or ball race. L is a collar secured to-the head 0 by screws L which projecting" beyond the end of the head G is inclined as at D to correspond with the inclined underface of the flange of the sleeve H,between which. are lodged ball bearings M. The lower slotted end of the spindle D is provided with a square cut screw thread d", on which is mounted a nut N adapt-ed when adjusted to bear against the shoulders I of the respective jaws I thereby insurin the ali ment of the counter-bore cuttln edges at the end of the jaws. The on r face of the nut may also serve with the end of the spindle to limit the depth of the counter-bore by contact with the surface surrounding the latter. Having now indicated the several parts by reference letters the constrlmtion and 0 eration of the device will be readily un erstood.

When it is desired to drill a hole to receive a round headed screw the integral gripping jaws and counter-bore cutters are ad usted with reference to the drill so that the cutting end E of the jaws are lodged within the slotted end of the spindle D, as shown in Figures 4 and 5, that the cutting ends of the jaws may not enter the wood.

Whenit is desired to drill and counterbore, the nut N and milled head G are adjusted outwardly upon the spindle until the cutting ends of the jaws project beyond the end of the spindle sufliciently to provide for cutting a counter-bore of proppr depththe depth of the counter-bore eing limited through contact of the end of the spindle see Figure 1-With the surrounding surface of the wood. Having thus described my invention what I claim 1s: I

1. In a device of the'character described; a spindle provided with a central boreslotted to receive a plurality of 'aws; a rotatable head. screwed upon t e spindle adapted for lon 'tudinal adjustment thereon; a slidable s eeve provided with a pluralit of inclined longitudinal grooves and coupled to the rotatable head for longitudlnal adjustment upon the spindle; a p

rality of blades lodged respectively in the slots of the spindle having an inclined edge slotted to receive a plurality of 'aws; a rotatable head screwed upon 1: e spindle adapted for longitudinal adjustment thereon; a slldable' s eeve provided with a pluralit of inclined longitudinal grooves and coup ed to the rotatable head for longitudinal adjustment upon the spindle; ball bear- 1n gs between the end of the head and the slidable sleeve; a plurality of blades lodged respectivel in the slots of the s indle.having an inc ined ed e extendin into the inclined grooves of t e sleeve wlth an extenslon forming inclined edge of the blades also a cuttin edge at the end of said extension, adapte 10 a shoulder at the end of the to cut a counter-bore; a nut screwed upon the end of the spindle and against the shoulder of said jaws.

3. In a device of the character described; a spindle provided with a fcentral bore slotted to receive a plurality of 'aws; a rotatable head screwed upon t e spindle adapted for lon 'tudinal adjustment thereon; a slidable s eeve provided with a plurality of inclined longitudinal grooves and a projecting flange at its u per end; a collar secured to the rotatable liead with an inwardly directed flange overla ping the flange of the slidable sleeve; bal bearings between the flange of the rotatable head and slidable sleeve; a plurality of blades lodged respectively in the slots of the spindle having an inc ined edge extending into the inclined grooves of the sleeve with a cutting edge at the end of the blades, adapted to cut a counter-bore; a nut screwed upon the end of the spindle.

In testimony whereof, I this specification.

HOWARD E. JAYNES. 

